Question

Why can ethanol be considered both a Lewis acid and a Lewis base?

Answer 1

because, like water, it can both accept and donate lone electron pairs

Explanation:

Ethanol acting as Lewis acid :accepting electron pair

`CH_3CH_2OH` +`B:^-` `->` `CH_3CH_2O^-`+ `BH`

in this case the hydroxyl proton receives the electron pair from a strong base, producing the ethylate anion.

Ethanol acting as Lewis base: donating electron pair

`CH_3CH_2OH` + `H^+` `->` `CH_3CH_2OH_2^+`

in this case the hydroxyl oxigen gives an electron pair to a strong acid, producing a protonated alcohol